*{
    font-family: 微软雅黑, Microsoft YaHei, sans-serif;
}

body{
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    overflow: hidden;
}

.clock{
    padding: 0 20px;
    min-height: 50px;
    background: rgba(0, 0, 0, 0.7);
    color: #fff;
    font-weight: bold;
    border-radius: 15px;
    text-align: center;
    line-height: 50px;
    font-size: 16px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

#sid{
    color: #4CAF50;
    font-size: 20px;
    padding: 0 5px;
}